MLive Muskegon Chronicle is covering the trial live, with updates as they happen posted in the comments section below this story.

The court day was scheduled to begin at 9:30 a.m. with Mason County Circuit Judge Richard I. Cooper's initial instructions to jurors, then opening statements by Mason County Prosecutor Paul Spaniola and defense attorney David Glancy. Prosecution witness testimony will follow.

Knysz, 20, of the Irons area is accused of shooting Butterfield in the head after the trooper pulled over Knysz and his wife, Sarah Renee Knysz, in a traffic stop the evening of Sept. 9 on Custer Road in rural Mason County.

Knysz is charged with murder of a peace officer, which carries a sentence of life in prison without possibility of parole; felony firearm, a consecutive two-year felony; and carrying concealed weapons and motor vehicle theft, both normally five-year felonies. He is charged as a second-time habitual offender based on a 2008 Lake County conviction of first-degree home invasion. That could boost the maximum sentence for the last two counts to 7½ years.

Sarah Knysz, 21, pleaded guilty as charged to accessory after the fact to a felony and car theft. Cooper sentenced her Dec. 10 to prison for two to five years for the accessory count and a concurrent 11 months for car theft.

As part of her plea agreement, Sarah Knysz agreed to testify against her husband. At her guilty plea Nov. 5, she told the judge that the couple were in his father's pickup truck, returning to Irons where the father lived, after selling some guns in Ludington that Eric had allegedly stolen from his father. Some guns were still in the car.

At about 6:20 p.m., Butterfield pulled them over. The 43-year-old trooper reportedly walked to the driver’s window and started to say something like “How’s it going?” Eric shot him before he could finish, Sarah testified. The trooper fell in the road, and they left.

At 6:23 p.m., a passing motorist called 911 to report finding Butterfield on the ground. Butterfield was airlifted to Traverse City's Munson Medical Center, where he died that night.

Based on information Butterfield had relayed to dispatch about the vehicle he stopped, police began to seek Eric Knysz as the suspect, according to police. Police located the couple at a gas station and store in Manistee County, by this time with an allegedly stolen car, at approximately 8:25 p.m. Eric Knysz allegedly pulled a gun when confronted by police and was shot in the leg. He's been charged with felonies in Manistee County.

John
S. Hausman covers courts, prisons, the environment and local government for
MLive Muskegon Chronicle. Email him at jhausman@mlive.com and follow
him on Twitter.